Strand testing machine



April 14, 1953 R. H. LAWSON STRAND TESTING MACHINE 5 Sheets-Sheet 2Filed Aug. 9, 1946 [wan/rm EZaeaZtZZZauavn April 1953 R. H. LAWSON2,634,607

STRAND TESTING MACHINE Filed Aug. 9, 1946 5 Sheets-Sheet 3 INVENTOR.220$e22ZZW April 14, 1953 R. H. LAWSON STRAND TESTING MACHINE 5Sheets-Sheet 4 Filed Aug. 9, 1946 INVENTOR.

Patented Apr. 14, 1953 GFFHCE STRAND TESTING MACHINE Application August9, 1946, Serial No. 689,559

6 Claims. (01. 73-460) This invention comprises a machine for testingtextile strands in order that they may be subsequently used withassurance that they have the characteristic requirements of elongation,strength and elastic power necessary for their intended purpose.

The machine of my invention may be organized for testing strands bysubjecting them either to a predetermined elongation or to apredetermined tension, and for testing strands that are eitherstretchable or non-stretchable. For example, in winding golf balls ofrubber thread, an elongation of ten to one is often specified and it istherefore important to ascertain that all rubber thread delivered to thewinding machine is capable of withstanding such elongation withoutbreaking. If breakage occurs in the winding machine, the winding cost isincreased and goods of inferior quality produced. The same problem isencountered in textile machinery where stretchable strands are to beemployed in weaving and spinning. In addition to rubber thread, rubbercovered thread and rayon and nylon thread are purposely or incidentallysubjected to elongation, and in these instances it is Very desirable toemploy strands which have been tested and proved capable of the requiredelongation with a comfortable margin of safety.

With these ends in view, the present invention in one aspect comprises acontinuously operating machine through which the strand to be tested maybe run at high speed and Without requiring any substantial amount ofskill or attention on the part of the operator, and in which the strandis subjected to a definite predetermined amount of stretch by beingelongated to a degree which thoroughly tests it, meanwhile continuouslyindicating the instantaneous tension of the strand and actingautomatically to stop in case of breakage.

When organized for that purpose, the machine of my invention comprises astrand feeding head rotated at a predetermined peripheral speed incombination with means for feeding an elastic strand to the head at arate of speed bearing a predetermined fractional ratio to the peripheralspeed of the head. Preferably and as herein shown, I employ two rotarystrand-feeding heads driven at different rates of linear speed. Aweighted member may be employed for engaging the strand as it passesfrom one head to the other and indicating the instantaneous tensiontherein. Automatic stopping means are also provided which act upon thestrand tensioned between the two heads for stopping the machine in caseof breakage.

In another aspect my invention comprises a machine in which the rotationof one of the strand-feeding heads is retarded so that a controlledamount of tension is developed in the strand passing from one to theother. This result may be accomplished by gearing introduced between thetwo heads, in which case the strand is subjected to a controlledelongation and tension, or by a brake acting on the in-feeding head, inwhich case the strand is subjected to a controlled amount of tension.

Other features of the invention relate more specifically to features ofthe strand feeding heads. These are preferably of the capstan typedisclosed in U. S. Letters Patent No. 1,847,161, March 1, 1932, Alden,and comprise a set of threaded spindles which rotate collectively withthe head as well as individually, with the result that the various turnsof the strand around the capstan are maintained out of engagement witheach other during the pulling or advancing movement. I have found thatthe accuracy of operation and life of such strand feeding heads aresubstantially improved by providing a rotary member for supporting theouter ends of the threaded spindles thus holding them accurately againstdeflection from their proper axes of rotation and substantially reducingWear on their bearings.

Going more into detail, I have found it also desirable to provide meansfor supporting the thread spindles against circumferential displacement.As herein shown,- such means may comprise radially projecting armsextending on both sides of each threaded spindle, being normallyarranged to clear the spindle but located permanently in position toarrest and prevent any circumferential displacement, particularly suchas might otherwise occur at the outer ends of' the spindles.

These and other features and advantages of the invention will be bestunderstood and appreciated from the following description of a preferredembodiment thereof, selected for purposes of illustration and shown inthe. accompanying drawings, in which:

t Fig. 1 is a View of the machine in front elevalOIl,

Fig. 2 is a view inelevation of the clamping device for the indicator asseen with its cover removed,

Fig. 3 is a sectional view on the line 3-3 of Fig. 2,

Fig. 4 is a plan view of the machine,

FEE? '5 is a sectional view on the line 55 of 1g.

head Fig. 6 is an end view of the machine showing a portion of thecasing broken away,

Fig. 7 is a sectional view on the line 'I-'! of Fig. 5,

Fig. 8 is a wiring diagram of the machine,

Fig. 9 is a view in perspective of a winding head of modifiedconstruction,

Fig. 10 is a fragmentary view of the same,

Fig. 11 is an end view,

Fig. 12 is a view of the machine in front elevation modified to subjectthe strand to controlled tension, and

Fig. 13 is a sectional view on the line I3I3 of Fig. 12.

The machine in its illustrated embodiment comprises a rectangular baseIt] from which rises a front plate I I carrying the moving parts of themachine and being provided with a cover plate I2 which is removablysecured to the base plate by bolts having knurled nuts I3. A drawing-inhead I4 and a strand delivering head I5 project forwardly from the frontplate I I at substantially the same level. These heads are identical inconstruction except that the head I5 is located further out from theface of the plate I I than the head It so that a strand passing from theouter ends of the spindles I6 of the head I4 will follow a straight pathin reaching the inner ends of the spindles I6 of the head I5 without thenecessity of a guide.

As shown in Fig. 5, each spindle It has a shaft of reduced diameterwhich is mounted in needle bearings I! in the head I4, and each shaft isprovided with a pinion I 8 acting as one member of a planetary systemincluding a central gear I9 which is held stationary by being pinned toa collar bolted to the front plate II. Ihe gear I 9 is provided on itsrear face with a sleeve 2!! which fits into the stationary collar 25which is bolted to the front plate II and supports the entire strandfeeding head. Passing through the sleeve 20 is a central shaft 2|journaled in needle bearings 22 which are mounted in a bushing set inthe front plate I I. The shaft 2] is fastened by a set screw 23 to a hubformed on the head I4 and drives the head with its six threadedspindles, the latter. being also individually rotated by the planetarygearing above described.

At its outer end the shaft 2I carries a supporting disk 24 contacting atits circumference with all of the spindles I6 and by rolling contactholding them positively against inward radial displacement, Theprovision of the supporting disk not only reduces wear on the spindlebearings but maintains them accurately in position and eliminates lostmotion therein.

At its inner 'end the shaft 2I carries a driving pinion 2'I meshing withan idle pinion 28 rotatable with an intermediate shaft 29 journaled inthe front plate and carrying also a large gear 30. The gear 30 in turnmeshes with a gear 3I fast on a second intermediate shaft 32 projectingforwardly from a swing plate 33 pivotally mounted to swing about ahorizontal axis provided by the shaft 2I' of the strand delivering I5.The shaft 32 projects outwardly through a segmental slot 35 describedabout the axis of the strand delivering head I5. The plate 33 carriesalso a short shaft on which is mounted a pinion 3I meshing with thepinion 3| and also with the pinion 38 upon the inner end of the' shaft2I' of the head I5. This shaft carries also a larger pinion 39 meshingwith the pinion no carried by a shaft of a. motor 4| which is supportedby the rear portion of the base In as shown in Fig. 6.

The shaft 32 of the swing plate 33 is provided with a knurled nut 36 bymeans of which the plate may be clamped in any desired position ofadjustment causing the gears of the train properly to mesh. It will benoted that the 'gear 30 is removably attached to its shaft 29, and thusthe machine has provision for the convenient substitution of varioussets of change gears by which the ratio of the linear speed of the twoheads I4 and I5 may be varied and the strand passing between themsubjected to varied amounts of stretch.

The tension of the strand passing between the two heads is measured andindicated by mechanism which will now be described. The front plate IIis provided with a boss in which is journaled a short horizontal shaft42. On the forward end of the shaft 42 is fixed a rod 43. The end of therod is forwardly offset as shown in Fig. 4 and carries a grooved roll44! which rides upon the strand passing between the two heads. From theouter end of the rod 43 is suspended a weight 45 and this is readilyreplaceable by weights graduated in accordance with the work in hand.The shaft 42 carries a hollow disk 46 having perforated radial bafiles4? and containing a charge of mercury 48 or other heavy liquid. Thisdisk acts to damp the oscillation of the rod 43 and prevent the disk Mfrom dancing upon the strand. It will be understood that the charge ofmercury tends to hold the disk 66 in whatever position it assumes andits retarded flow through the perforations of the bafiles 3! retardsmovement of the shaft 32 and its associated parts. The shaft 42 alsocarries a pointer 49 which, by its displacement, indicates on itssegmental scale 50 the instantaneous tension in the strand. From theforegoing description it will be seen that the greater the sag made inthe strand by the roll 44, the lower will be the reading of the scaleand the lower will be the tension in the strand. If desired the movementof the pointer 49 may be recorded so as to provide a permanent record ofeach tested strand.

The shaft 42, in addition to its function in the indicating mechanism,is utilized also to operate an automatic stop. For this purpose it isprovided at its end with a segment 52 whichnormally supports in elevatedposition a collar 53 upon the lower end of a plunger controlling anelectric microswitch 54 which, as shown in Fig. 6, is secured to the topof the casing I I. The microswitch is interposed in the main linecircuit to the motor as shown by the diagram of Fig. 8. Also included inthis circuit is a stopping and starting switch controlled by a button 55which projects through the upper lefthand portion of the front plate II.

In operation the strand is led through a fixed eye 56 set in the plateII and serving to guide it to the drawing-in head I4. It is passedseveral times about the groove of spindles I6, and then led to thedelivering head I5, passed several times about the spindle I6, and fromthere led out of the machine. The change gears having been adjusted forthe desired testing elongation, the roll M is rested upon the strand asrunning under tension between the two heads, and the machine set inaction. Thereupon the strand is rapidly and continuously fed through themachine, subjected temporarily to the desired amount of elongation, anddelivered after having been thus tested. Meanwhile the pointer 49indicates the instantaneous amount of tension resulting from theelongation of the strand. In case of breakage the weighted rod 43, nowunsupported, immediately rocks the shaft 52 carrying the segment 52beyond the drop-off point. The switch plunger is thereupon permitted tomove downwardly and the circuit to the motor is broken.

In Figs. 9-11 is illustrated a head of somewhat modified constructionwhich may be substituted for either of the heads Hi and I5 abovedescribed. The principal difference is that in these heads the threadedspindles are afforded circumferential as well as radial support. To thatend the head 60 is recessed in its outer face to receive a shoulderedstud 6! having at its outer end a seriesof radial projections 62arranged to fit into the spaces between the threaded spindles 63 andform a series of individual guide pockets for each spindle servingpositively to prevent displacement of the inner end or intermediateportion of the spindle. The stud BI is secured to the head 60 by anysuitable means such as axial screws, one of which is shown in Fig. 10.The stud 6| is bored axially to receive the center shaft 64, and uponits outer end this shaft carries a disk 65 which engages the spindles 63near their outer ends and supplies radial support to them.

The spindles 63 as well as the spindles l6 and I6 are shown herein ascarrying pinions which have a 1 to 2 ratio with respect to the largestationary gear 19. Accordingly, each spindle makes two individualrotations and is rotated once in its movement with the head for eachcomplete revolution of the head. In other words, each spindle makesthree complete rotations for one rotation of the head. The result isthat the turns of the strand wound about the group of spindles are keptwell separated while the machine is operating. This constructionalfeature has been found to be particularly advantageous and effective inguarding the strands against crossing or interference.

The machine has been heretofore described as it is organized forsubjecting an elastic strand to a predetermined amount of elongation andwhen so operating it will be clear that the speed of rotation of thein-feeding head i4 is retarded and held back with respect to the speedof rotation of the delivering head l5 by the gearing which is interposedbetween these two heads.

In Figs. 12 and 13 is shown the machine as organized for subjecting thestrand to a controlled amount of tension. When so organized, thedelivering head I5 with its threaded spindles l6 and center spindle 2|are driven directly by the motor ii through the gearing alreadydescribed. The in-feeding head, however, is not driven but is under thecontrol of a band brake. In the illustrated machine, the front plate l iis provided with a projecting circular bos 19 in which is mounted astationary bushing H to which is attached the stationary central gear'12 of the planetary system. A spindle i3 is journaled in the bushing lland in the boss l as shown in Fig. 13, and to this spindle is pinned thehead 14. In the head is mounted a group of threaded spindle 15, each ofwhich carries a small gear l6 meshing with the central gear 72. At itsouter end the spindle 13 carries a support disk ll which makes rotarycontact with the spindle l at their outer ends.

The head 74 is enclosed within a stationary segmental shield '58. Withinthe shield is located a band brake 19 which is V-shaped in cross sectionand fits into a circumferential groove of the same shape in the head 14.The brake is conn'ected at one end to a screw 80 projecting from thefront plate II and at the other through a flexible cable 81 to thesha'ft '42 of the indicator. The shaft 42 carriesa'n arm 43 providedwith a roller 44 having a weight '45 and arranged to run on the strandas it passes from one head to the other. The shaft 42 also carries apointer which cooperates with the segmental scale 50 to indicatethe'instantaneous tension in the strand.

It will be seen that themechanism above described operates to increasethe drag of the brake as the tension in the strand decreases with theresult that the tension of the strand is thereby increased. On the otherhand, as the tension in the strand increases the arm 43 is lifted andthe drag of the brake reduced, thereby reducin the tension in thestrand. The brake and the weight may be adjusted so that a balancedoperating condition is secured in which the strand is subjected to asubstantially uniform tension in passing from one head to the other. Ifthe strand is elastic the elongation may be variable, but whether or notthe strand is elastic it is subjected to substantially uniform tension.

Having thus disclosed my invention and described in detail severalillustrative embodiments thereof, I claim as new and desire to secure byLetters Patent:

1. A strand testing machine comprising a rotary strand-feeding head, amotor connected to the head for driving it at a uniform rate of speed, asecond strand-feeding head spaced from the firstmentioned head, a trainof gears interposed between the two heads for driving the secondstrandfeeding head at a slower rate of speed than the first-mentionedhead, and a swing plate carrying one gear of the train wherebysubstitution may be made for adjusting the relative speeds of the twoheads to vary the tension of a strand passing from one to the other.

2. A strand testing machine comprising a 1'0- tary head including aplurality of threaded strand-feeding spindles carried by the head andplanetary gearing connecting said spindles, a second strand-feeding headsimilarly equipped with threaded spindles, means for driving the headsat different linear speeds to tension a strand passing from one head tothe other, and means continuously indicating the tension of a strandpassing from one set of spindles to the other.

3. A strand testing machine having a pair of rotary feeding devicesgeared to advance an elastic strand at diiferent linear rates of speed,a motor for driving said devices, a movable detector mounted to rideupon the strand as it passes from one feeding device to the other, aswitch controlling said motor and a tension indicator, both the switchand the indicator being governed by said detector.

4. In a strand testing machine having a pair of spaced strand feedingheads located at substantially the same level and geared to rotate atdifferent speeds, indicator mechanism comprising a movable arm carryinga roll arranged to ride on the strand in passing from one head to theother, and a hollow member having perforated bafiies therein and apartial filling of liquid and bein connected to said arm and turnedtherewith.

5. A strand testing machine comprising a frame carrying a pair of spacedstrand-feeding heads, a motor connected to one of said heads, a swingplate mounted for movement about the axis of one head, and a gear trainconnecting said heads for rotating them positively at different speedsincluding gears mounted on said swing plate.

References Cited in the file of this patent UNITED STATES PATENTS NameDate Serrell 1 May 5, 1885 Number Number 772,090 1,742,953 1,786,917

Number 8 Name Date Duquett 11 Oct. 11, 1904 Gahlert et a1 Jan. 7, 1930Oehmichen Dec. 30, 1930 Roller May 12, 1931 Alden Mar. 1, 1932 CornetMar. 29, 1932 Murphy June 5, 1934 Bouhuys Sept. 7, 1937 Jordan Dec. 24,1940 Heinz Nov. 13, 1945 Henry July 22, 1947 Symmes Feb. 24, 1948FOREIGN PATENTS Country Date Great Britain Nov. 6, 1863 Germany May 30,1939 France Mar. 18, 1935

